docs: def scan(backend, timeout=10):
      """Scan for miflora devices.
  
      Note: this must be run as root!
      """
      result = []
      for (mac, name) in backend.scan_for_devices(timeout):
          if (name is not None and name.lower() in VALID_DEVICE_NAMES) or \
                  mac is not None and mac.upper().startswith(DEVICE_PREFIX):
              result.append(mac.upper())
      return result